Tool for making cartridge shells



, June 4', 1 935. A. GUIGNET TOOL FOR MAKING CARTRIDGE SHELLS OriginalFiled March 1. 193s 2 Sheets-Sheet l Inventor Z, co/v Ill/ 05 Guignet'June 4, 1935.

| A. GUIGNET TOOL FOR MAKING CARTRIDGE SHELLS Original Filed March 1,1933 2 Sheets-Sheet 2 fitta r71 ey.

Patented June 4, 1935 UNITED STATES PATENT OFFICE TOOL FOR MAKINGCARTRIDGE SHELLS Lon Auguste Gnignet, La Varenne Ste. Hilaire,

France, assignor to Asturienne des Mines, tion of Belgium The CompagnieRoyale Paris, France, a corpora- Original application March 1, 1933,Serial No.

659,115, now Patent No. 1,974,270, dated September 18, 1934. Divided andthis application September 9, 1933, Serial No. 688,760. In GermanyJanuary 17, 193

3 Claims fold in the shell between the base and the tubular part of theshell, the crowns of said. fold having a relatively large radius ofcurvature so as to readily withstand the internal gas pressure uponfiring.

The present invention has for its object a tool for manufacturing shellsof this character.

Another object is to provide a tool by which said shells can bemanufactured expeditiously and with a minimum number of operations.

Other objects and advantages will hereinafter appear.

The accompanying drawings illustrate, by way of example, aconstructional embodiment of the new tool and its operation.

In the drawings Figure 1 is a longitudinal cross section of the lowerpart of a completed shell having a relatively thick bottom portion and arelatively thin side portion of substantially uniform cross section.

Fig. 2 is a longitudinal section of an intermediate form of a shellduring its manufacture and prior to its insertion in the present toolfor the finishing operation.

- Fig. 3 is a longitudinal section of the tool while the shell blankillustrated in Fig. 2 is being inserted.

Fig. 4 is a longitudinal sectionof the tool at the end of the formingoperation of the completed shell.

Fig. 5 is a detaiLcross section of parts 6, 6 on line 55 in Fig. 3,looking in the direction of the arrows Referring to the drawings, thesame illustrate a tool for the final conversion of a unitary shell blankas illustrated in Fig. 2 into a completed cartridge shell as illustratedin Fig. 1, said shell having a tubular side wall I of either constant orof tapered cross section'which is merged into a base 2 of preferablygreater thickness than the wall I through a double fold consisting of anouter convolution 4 and an inner convolution 5, the cross section of theconnection between the convolution 4 and a bottom rim 3 being preferablytapered and the crowns of both convolutions of tne fold having a;substantial radius in cross section so as not to cause overstraining oithe material during formation and when subjected to internal. pressureupon firing.

The tool consists of two portions, the upper portion A being preferablyarranged for mounting on the rain of a drawing or punching press, whilethe lower portion B is preferably arranged for fastening to thestationary platen of the press.

The portion A is provided with a longitudinalconical central boreadapted to receive a frustated conical liner 6 which is radially dividedinto two halves as indicated by' Fig. 5. The liner is provided with acentral bore l9 approximately corresponding to the outside diameter ofthe shell blank. Arranged inside of said bore is a mandril I, having acollar 20, said mandril being fixedly attached to the body of the partA.. The axial length of the liner 6 is slightly less than thecorresponding bore in the body A'so as to provide a space I! between theupper end of the liner and vthe collar 20, said collar being recessed inthe body A so as to form an abutment for the mandril 1 and also for theliner 6 so as to limit the lateral movement of the latter with respectto the body A. Y V

The lower end of the mandril 'l is provided with a bevel H of such shapeas to aid in the formation of the inner fold or convolution 5 of the.shell. The mandril 1 has a central bore in which is slidably mounted anejector pin 9, the upper part of said ejector pin being provided with aI collar which limits its downward movement. The

ejectorpin is urged downwardly by a spring 8. The diameter of themandril I is such as to correspond to the inside diameter of the shell,thus providing fora space between themandril and the liner for theintroduction of a shell blank as illustrated in' Figs. 2 and 3. A recessI0 is provided at the lower end of the bore IQ of the liner 6 of suchshape as to facilitate the formation of the outside fold or convolutionof the shell. In the downward direction the liner is prevented fromsliding out of the body A by means of a collar l8 having a bore 18 ofsuitable diameter.

The lower part B of the tool is provided with an annular flange or ringI which is slidably guided in said body by means of a number of rods I5.The upward movement of said flange is limited by a number of screws II.The rods list their lower free end abut against a-colllar it which isurged upwardly by means of a heavy spring l3. In a central bore of theflange H is slidably mounted a plunger l2, said plunger being fixedlyattached to the body B. The bore I8 of the upper part of the tool is ofsuch diameter as to pass the upper end of the flange I4 and permit it tobear against the liner 5.

The shell consists of a tubular part I and a raise u 2. The blank isfirst drawn in the usual manner, the bottom having a constant thicknesswhich may be greater than that of the tubular part and the wall of thetubular part may be slightly ta;- pered or may be straight. It will beunderstood that the portions shownin Figs. 1 and 2 are somewhatexaggerated. As an example, the thickness of the top end of the tubularpart may be .23 mm., while the thickness of the tubular part near thebase may be .3 mm., and the constant thickness of the base may also be.3 mm., or may have a thickness of as much as .7 mm., the latterproportion approximately corresponding to th proportion shown inparagraph 1. The tool-operates in the following manner: After the shellblank I is inserted in the upper part A of the tool as illustrated inFig. 3, the ram of the press is lowered and the upper part A movedtowards the lower part B. The shell is pushed into the recess l9approximately to the point where its base 2 abuts against the ejectorpin 9. Approximately at the same time the flange l4 touches the lowersurface of the liner 6 so that upon further downward movement the flangeis urged downward against the pressure of the spring l3. As this springpressure is relatively high, it resists the downward movement of theflange and causes movement of the liner longitudinally in the part A andthus causes the latter to close in radially on the tubular part of theshell I so as to press it tightly against the mandril I and prevent itfrom further upward movement. The liner slides in the part A until theair gap I! has been closed, whereupon its turther longitudinal movementis prevented by abutment against the collar 20. Upon further movement ofthe part A, the spring I3 is compressed by the downward movement of theflange H and ultimately the shell blank makes contact with the plungerI2. This plunger thereupon drives the material of the shell upwardly andcauses it to fold, said folding being guided by the recesses l0 in theliner 6 and the bevel ll of the mandril I. The bore Ill also determinesthe outside diameter of the shell rim. The relative position of thetools is ultimately as illustrated in Fig. 4 in which the shell has itsfinal shape. Thereafter the ram of the machine is raised and the parts Aand B separate again. This movement finally releases the upward pressureon the liner 6 and the latter opens up radially and permits the shell tobe ejected from the part A by the action of the spring 8 on the ejectorpin 9, the spring having been previously compressed by the upwardmovement ofi the base of the shell and of the ejector pin 9 aftercontact of the base with the plunger l2.

The described apparatus produces a shell from a blank in a singleoperation instead of a number of complicated and difiicult operationsrequired by other known means. It further assures a shell,

the material of which has not been subjectedto manufacture of othertypes of shells than the one herein illustrated and described and Itherefore do not wish to limit the appended claims to a tool formanufacturing the shell illustrated herein.

What I claim as new and desire to secure by Letters Patent is:

' 1. A tool for the production of a double fold between the bottom andthe side of a unitary cartridge shell, comprising an upper part, saidupper part comprising a mandril for said shell, having a beveled lowerend adapted to produce the inner convolution of said fold uponapplication-of an axial thrust upon said shell, a divided liner shapedandadapted to move radially to grip said shell and having a recessadapted to produce the outer convolution of said told upon applicationof said thrust, and a lower part, the latter comprising a fixed plunger,a relatively movable flange surrounding said plunger, and

adapted'to engage said liner to cause it to move laterally and a biasingspring tending to oppose movement of said flange. I

2. A tool for, the production of a double fold between the bottom andthe side of a unitary cartridge shell, comprising an upper part, saidupper part comprising a mandril for said shell havinga beveled lower endadapted to produce the inner convolution of said fold, a spring biasedelement concentric with said mandril tending to push said shell out ofengagement therewith, a divided liner shaped and adapted to moveradially to grip said shell and having a recess adapted to produce theouter convolution of said fold, and a lower part, the latter comprisinga fixed plunger, a relatively movable flange surrounding said plunger,and adapted to engage said liner to cause it to move laterally and abiasing spring tending to oppose movement of said flange.

3. A tool for the production of a double fold between the bottom and theside of a unitary cartridge shell, comprising an upper part, said upperpart comprising a mandril for said shell, having a beveled lower endadapted to produce the inner convolutions of said told upon applicationof an axial thrust upon said shell, a spring biased element concentricwith said mandril LEON AUGUS'I'E GUIGNET.

